Many plants are made easier to identify by their flowers. Flower field guides are generally organised by colour, and amateur botanists of all ages can normally make an identification fairly quickly. Many nature lovers have a more difficult time when it comes to identifying flowering plants when not in bloom. Flowering plants can be identified by their leaves as well as their flowers, though this takes a bit more patience and consideration. Knowledge of the different types, shapes and organisation of leaves becomes more important in the absence of flowers.
Become familiar with the types of flowering plants in your area by talking to botanists or browsing a field guide. Not all plants grow in all conditions and geographic regions, and knowing what types of flowering plants to expect can aid you in identification.
Learn the terminology of leaves by consulting a field guide or botany textbook, which can be found in most libraries. Inaccurate or vague notes can cause confusion, so you must use the correct labels when describing leaves. For example, what we think of as being the leaf of a plant is referred to as the "blade," which attaches to the stem through the "petiole," or stalk. The edge of the blade is referred to as the "margin" and tip is the "apex."
Determine if the flowering plant has compound leaves or simple leaves and make a note of this. Simple leaves are composed of only one leaf blade, while compound leaves are divided into leaflets, which all share the same petiole. An easy way to tell the difference is that a single leaf has a petiole with a bud at the base, whereas leaflets do not.
Take notes on observations you have regarding the leaf blades. Make note of their size, shape, colour, number, placement and whether they have smooth, toothed or lobed margins.
Make a note of how the petioles are attached to the stem of the plant. Write down whether the leaves are arranged opposite one another on the stem, or whether they are alternate.
Draw a quick sketch of the plant. This sketch does not need to be artistic, but it does need to be fairly accurate in regard to the shape, size and placement of the leaves on the plant.
Use an identification key and the field notes you have taken to determine the type of flowering plant. An identification key can be found in most field guides.
Taking a photo of a plant, in addition to making detailed notes, can aid in later identification.
Never remove plants from their native environment.